The present invention relates to a failover method which switches a server in operation to a standby server upon occurrence of a failure in the server in operation, and, in particular, to N+1 cold standby.
One way to secure reliability of a server system is to configure a multiplexed server. By installing a standby server different from a server in operation, if a failure occurs in the server in operation, it switches to the standby server to take over the operation.
There are various ways to configure a fault tolerance configuration. For example, there is a method that arranges servers redundantly in a network, each server monitors another server without overlapping with other servers once in every monitoring cycle, and an active server switches to a standby server when failure occurs in the active server (refer to JP 2006-229512 A).
Moreover, there is a method which determines the order of the processing according to the priority of the node, and avoids the delay of the succession processing for nodes that have high priority (refer to JP 2007-279890 A).
Since early times, there has been a need to improve the reliability of a server system at a low cost. One way to improve the reliability of a server system at a low cost includes “cold standby”.
As for cold standby, a plurality of servers having the same system configurations are provided, and when one server performs an operation, the other servers wait idle in a standby state. In a case where a failure occurs in the active server in operation, the standby server device starts up and takes over the operation.
However, cold standby requires having a management server and does not satisfy the above requirement.
One method to solve this problem includes running a management program which performs processing equivalent to the processing executed in a management server in the active server and managing the overall servers.